The Department of Justice (DOJ), the lead agency that oversees the Americans with Disabilities Act (ADA), has mandated that many municipalities and other governmental bodies comply with certain regulations regarding accessibility. One such regulation deals with accessibility on walkways in public right of ways. In brief, it requires that surfaces of those walkways enable tactile detection by visually impaired persons.
One of the primary ways of providing the ability to detect proximity to hazardous locations (e.g., roadways, railroad crossings, etc.) is by modifying the surface texture of the walkways. Tactilely detectable warnings are distinctive surface patterns of domes detectable by cane or underfoot, and are used to alert people with vision impairments of their approach to streets and hazardous drop-offs. The ADA Accessibility Guidelines (ADAAG) require these warnings on the surface of curb ramps, which remove a tactile cue otherwise provided by curb faces, and at other areas where pedestrian ways blend with vehicular ways. They are also required along the edges of boarding platforms in transit facilities and at the perimeter of reflecting pools.
Complying with the federal mandate is requiring the expenditure of much time and money by the municipalities to modify the surface textures of their sidewalks and other walkways. The need for a tactile warning device that is cost effective is essential to enable municipalities to comply with the ADA unfunded mandates. It is also needed by non-governmental entities, such as land developers, railroad companies and others who likewise need to provide tactile-detectable surfaces at curb ramps, platforms and the like.
Some embedded tile devices currently exist for providing tactilely detectable warning surfaces for the visually impaired in concrete walkways. Once embedded in moldable walkway materials such as concrete or asphalt, these devices form a truncated dome portion of the surface that is detectable to people on foot.
However, most of these devices are made out of plastic and are flimsy, being subject to ultraviolet light damage, deterioration and cracking in short periods of time. Also, inherent to the truncated dome design is the exposure of domes to severe impacts by snowplow equipment, particularly snowplow blades and end-loader buckets. Domes made of plastic tend to be sheared off, nicked or cracked when snowplows hit them. Once damaged, repair requires that entire plastic embedded tiles be removed and replaced. The fact that plastic embedded tile devices are easily damaged results in high long-term costs to maintaining truncated dome surfaces when they are employed. Yet, current manufactures of plastic embedded tile devices either do not warrant the devices or warrant them for no more than five years. Public entities cannot afford to replace truncated dome devices every five years—nor every ten to fifteen years for that matter. A more durable device is needed.
Information somewhat relevant to attempts to address these problems can be found in U.S. Pat. No. 5,775,835 to Szekely; U.S. Pat. No. 6,449,790 to Szekely; U.S. Pat. No. 6,715,956 TO Weber et al.; and, U.S. Patent Application Publication US 2004/0042850 to Provenzano, III. However, each one of these references suffers from one or more of the following disadvantages: (1) they do not enable embedment of a tile in moldable materials such as concrete or asphalt; (2) they lack means for securely interlocking a tile with the moldable material; (3) they result in build-up of moldable material around the edges of the tile when inserted, resulting in longer installation times due to the need for removal of the buildup prior to finishing; (4) the tiles do not provide means for internal air release and therefore allow trapped air pockets to obstruct the efficient movement of air and moldable material when the tile is sunk, making embedment more time-consuming and difficult, and often requiring the application of weights to prevent the tile from floating while the moldable material sets; and, (5) the tiles are not made of materials that stand up to the cracking and sheering effects of snowplows or other heavy equipment, thus resulting in high maintenance costs over time.
For the foregoing reasons there is a need for an embedment tile device that is designed to be both easily installable to minimize installation time and cost, and durable to minimize long-term maintenance costs and to reliably provide tactilely detectable surfaces.